Int 16 Fn F400  - Compaq Systempro And Higher - Cache Controller Status    [b]

   AX = F400h

Return: AH = E2h (*)
   AL = status
       00h not present
       01h enabled
       02h disabled
   CX = cache memory size
       bit 15: cache size information is NOT valid
       bits 14-0:  cache memory size in kilobytes
   DH = cache write technology
       bit 7:  cache write information is NOT valid
       bits 6-1:   reserved (0)
       bit 0:  0 = Write-through caching
           1 = Write-back caching
   DL = cache type
       bit 7:  cache type information is NOT valid
       bits 6-1:   reserved (0)
       bit 0:  0 = Direct mapped
           1 = Two-way set-associative

Notes: also supported by some versions of AMI BIOS dated June 1992 or later
   many (most) BIOSes return a modified AH when called for an unsupported
     or non-keyboard function (typically, the highest supported keyboard
     function [normally 12h] is subtracted from the original AH)

See Also: AX=F401h,AX=F402h